Search PubMed⌕ Search

Biomedical subjects

I Ando

Publications and source records attributed to I Ando.

At least 55 records · Page 3Linked to original sources
PubMed1988

Biodistributions of radioactive alkaline metals in tumor bearing animals: comparison with 201Tl.

The retention values for 42K, 86Rb and 134Cs in the tissues and blood were quite similar to those for 201Tl, but were very different from those for 22Na. In an experiment for subcellular fractionation of tumors, most of these nuclides were localized in the supernatant fraction, with small amounts in other fractions. The concentration ratios for these nuclides in each fraction were approximately constant regardless of the time after administration. Radioactive alkaline metals in the supernatant fraction of the tumor homogenate existed mostly as free ions and were bound to protein in other fractions of tumor tissue. These results were essentially the same as those for 201Tl. Ouabain suppression studies indicated that 201Tl is taken up into the tumor cells partly through Na+, K+-ATPase of their membranes. Ionic radii of alkaline metals and thallium were related to their blood and tumor retention values. This relationship suggested that monovalent cations whose ionic radii exceed 0.133 nm, and which exist as free ions in the tissue fluids, behave like the potassium ion. Potassium and K analogs (Tl, Rb, Cs) are avidly taken up into viable tumor cells whose Na+, K+-ATPase activity is elevated. Therefore, suitable radionuclides of K and K analogs can be excellent agents for visualization of viable tumor tissues.

Animals↗
PubMed1988

Distribution of 103Ru-chloride in tumor-bearing animals and the mechanism for accumulation in tumor and liver.

Tumor uptake rates of 103Ru-chloride were smaller than those for 67Ga-citrate. In three tumors and liver, 103Ru in the mitochondrial fraction containing lysosome increased with time after the administration of 103Ru-chloride. The concentration of 103Ru was more dominant in connective tissue (especially inflammatory tissue) than in viable tumor tissue or in necrotic tissue. Quite large amounts of 103Ru in the tumor and liver were bound to the acid mucopolysaccharide whose molecular masses exceeded 40,000. Behavior of this nuclide was essentially similar to that of 67Ga.

Animals↗
PubMed1987

Ganglioside GM2 on the K562 cell line is recognized as a target structure by human natural killer cells.

Although human NK cells lyse a wide spectrum of target cells, the precise target structure recognized by NK cells has not yet been elucidated. In order to define a possible relationship between gangliosides on human target cells and susceptibility to NK lysis, 14 human leukemia and lymphoma cell lines were studied. A significant correlation was observed between the quantity of ganglioside GM2 on the target cells and sensitivity to NK lysis. In a single-cell binding assay purified GM2 specifically inhibited human NK cell binding to K562 target cells while other gangliosides did not inhibit binding. The competitive inhibition of NK cells by GM2 was restricted to the source of tissue from which GM2 was isolated. These results indicate that GM2 is a strong candidate as a target recognition structure for human NK cells.

Binding Sites↗
PubMed1987

Cortical thymocyte differentiation in thymomas: an immunohistologic analysis of the pathologic microenvironment.

Four monoclonal antibodies (BH11, T2/30, AG3, and BC3) were produced against different epithelial components of the normal thymus. An immunohistologic study was performed on 13 thymomas by the use of these and other stromal and lymphocyte-specific reagents. The aim of this study was to find possible relationships between the proliferating thymoma epithelial cell type and the T cell composition of thymomas. Our results indicate that cortical T cell differentiation is present in thymomas, and that this differentiation is induced in the absence of detectable levels of MHC class II antigens on the epithelial component in most cases. The role of the MHC class II antigens cannot be excluded, however, because these antigens were always present on macrophages. Analysis of the selected group of thymomas, each of which contained epithelial cells homogeneously stained by at least one of the described monoclonal antibodies, showed that the cortical type T cell inducer capacity of thymomas is independent of the epithelial type predominant in the tumor.

Antibodies, Monoclonal↗
PubMed1987

A simple microassay for interleukin-2 activity.

A simple in vitro assay is described to quantitate human interleukin-2 (IL-2). It is based on the spontaneous' activation of human peripheral T cells in tissue culture and the subsequent expression of the IL-2 receptor. The results obtained with this assay agree with those of assays which utilise IL-2 dependent T cell clones. The method is highly sensitive, reproducible and easy to perform.

Antigens, Differentiation, T-Lymphocyte↗
PubMed1987

67Ga accumulation in inflammatory lesion and its mechanism: comparison with malignant tumor.

The accumulation of 67Ga in inflammatory lesions increased with time after injection of turpentine oil and reached a plateau 5 days later. At that time the uptake in the lesions was larger than any other tissue, after ten days the lesion uptake decreased. In experiments using rats which had been kept for 5 days after subcutaneous injection of turpentine oil, the accumulation of 67Ga in inflammatory lesions increased with time until six days after administration of 67Ga-citrate. It is clear from this study that 67Ga is avidly accumulated in areas where the subcutaneous tissue is infiltrated with neutrophils and macrophages, that it is not accumulated at the sites in which neutrophils are crowded, that nuclear material, mitochondria, lysosomes and microsomes do not play a major role in 67Ga accumulation in the lesion and that the main binding acid mucopolysaccharide in the lesion is a acid mucopolysaccharide which is none of the following: keratan sulfate, heparan sulfate, heparin, or chondroitin sulfate A, B or C. It is presumed that the main 67Ga binding acid mucopolysaccharide is keratan polysulfate (or other oversulfated acid mucopolysaccharides).

Animals↗
PubMed1987

Biodistributions of 201Tl in tumor bearing animals and inflammatory lesion induced animals.

The accumulation of 201Tl in tumor and inflammatory tissues were small. However, this nuclide showed a high concentration in viable tumor tissue, less in connective tissue (containing inflammatory tissue), and was not seen in necrotic tumor tissue regardless of the time after administration of 201Tl(I)-chloride. In inflammatory lesions, 201Tl accumulated in subcutaneous tissue infiltrated with neutrophils and macrophages, and quite large amounts of this nuclide were accumulated in subcutaneous tissue and sites where neutrophils were crowded. Most 201Tl existed in a free form in the fluid of tumor and inflammatory tissues regardless of the time after administration. A small amount of this nuclide was localized in the nuclear, mitochondrial and microsomal fractions in these tissues, and the nuclide was bound to protein in these fractions. The distribution of 201Tl(III)-chloride in tumor bearing animals was essentially the same as that of 201Tl(I)-chloride.

Animals↗
PubMed1987

Distribution of 46Sc and 51Cr in tumor-bearing animals and the mechanism for accumulation in tumor and liver.

Tumor uptake rates, concentrations in mitochondrial fraction (containing lysosome) of liver and tumors, avid accumulations in connective tissue (especially inflammatory tissue) and binding substances in these tissues for 46Sc3+ and 51Cr3+ were essentially similar to those for 67Ga3+, 111In3+, 169Yb3+, 167Tm3+, 95Zr4+ and 181Hf4+. However, the main binding substance of 46Sc3+ and 51Cr3+ in tumor and liver was the acid mucopolysaccharide (as described concerning 95Zr and 181Hf) whose molecular weight exceeded 40,000, although the main binding substance of 67Ga3+, 111In3+, 169Yb3+ and 167Tm3+ was the acid mucopolysaccharide with a molecular weight of about 10,000.

Animals↗
PubMed1986

Pretibial epidermolysis bullosa. Successful therapy with a skin graft.

A patient with pretibial epidermolysis bullosa was successfully treated with a skin graft. Ultrastructural examination revealed a decreased number of and rudimentary anchoring fibrils (AFs) in the pretibial area in contrast to normal AFs in the grafted skin obtained from a nonpredilection site. Our results indicate the importance of AFs in the pathogenesis of pretibial epidermolysis bullosa.

Adolescent↗
PubMed1986

A single-strip mini-paper chromatographic method for rapid purity-control of 99mTc-labeled radiopharmaceuticals.

A single-strip miniaturized paper chromatographic method (Mini-PC) was developed using 80%-90% acetone solvent for rapid purity-control of 99mTc-radiopharmaceuticals. Routine 99mTc-radiopharmaceuticals (eight kinds of "kit" made agents) and diluted agents (in which radiochemical impurities might be formed) were analyzed by Mini-PC and other methods. This showed that, compared with the other methods, the Mini-PC technique is useful for the simple and rapid routine analysis of radiochemical impurities of "kit" made 99mTc-radiopharmaceuticals.

Chromatography, Paper↗
PubMed1986

Distribution of 95Zr and 181Hf in tumor-bearing animals and mechanism for accumulation in tumor and liver.

Tumor uptake rates, concentrations in the mitochondrial fraction (containing lysosome) of liver and tumors, avid accumulations in connective tissue (especially inflammatory tissue) and binding substances in these tissues of 95Zr and 181Hf were essentially similar to those for 67Ga, 111In, 169Yb and 167Tm. However, the main binding substance of the above elements in group IV in tumor and liver was acid mucopolysaccharide whose molecular weight exceeded 40,000, although the above elements in group III were bound mainly to the acid mucopolysaccharide with a molecular weight of about 10,000.

Animals↗
PubMed1986

Different pathways of human T-cell activation revealed by PHA-P and PHA-M.

Antigen-specific T-cell activation is mediated via the CD3-Ti (antigen receptor) complex, and monoclonal antibodies to both CD3 and Ti cause a rapid rise in intracellular Ca2+. This calcium mobilization is not inhibited by monoclonal antibodies to CD2. The rise in calcium mobilization induced by purified PHA (PHA-P) does not occur in a cell line which lacks CD2 expression, and can be blocked in other T cells by anti-CD2 antibodies. A combination of monoclonal antibodies to different epitopes of CD2 causes calcium mobilization and mitogenesis. Reagent grade PHA (PHA-M) induces calcium moblization in cells that lack CD2, and its effects in other T cells cannot be blocked by anti-CD2 antibodies. The effects of PHA-P and PHA-M are thus mediated predominantly through different activation pathways.

Antibodies, Monoclonal↗
PubMed1986

A family study of the X-linked lymphoproliferative syndrome: evidence for a B cell defect contributing to the immunodeficiency.

The X-linked lymphoproliferative syndrome (XLPS) is an immunodeficiency characterized by severe primary infection with the Epstein Barr (EB) virus, which is often fatal. This has been attributed to failure to generate T lymphocytes which are specifically cytotoxic for EB virus-infected B lymphocytes, and which develop in all normal individuals following primary infection. We have studied a kindred which carried the defective gene for XLPS and have confirmed that the pattern of serum antibody responses to EB viral antigens can be used to detect affected males and female carriers. Furthermore, an EB virus genome-carrying B cell line which grew spontaneously from a culture of bone marrow cells from a male child with XLPS at the time of primary infection showed a decreased sensitivity to MHC-restricted, EB virus-specific killing by a T cell clone when compared to its in vitro EB virus-transformed counterpart. From these results we suggest that a subset of EB virus-infected B lymphocytes which were resistant to EB virus-specific killing existed in this child, and may have contributed to the overwhelming EB virus infection and its fatal outcome.

Antibodies, Viral↗
PubMed1986

EB virus induction is associated with B-cell maturation.

EB virus genome-carrying B-cell lines have been double-stained for B-cell activation or maturation antigens and viral antigens using indirect immunofluorescence. The vast majority of cells express activation antigens, whereas the plasma cell antigen PC1 is present on only a few cells. Staining for this antigen doubles with staining for EB viral capsid antigen. Thus it marks cells in the virus replicative cycle, and these cells are negative for the EB virus nuclear antigen EBNA. We suggest that within EB virus genome-carrying B-cell lines the maturation of a few cells to the stage of expression of plasma-cell markers leads to the loss of EBNA expression and consequent loss of the immortalized state of the cell. This would allow completion of the lytic cycle with the production of virus particles and cell death. The implications of these findings are discussed.

Antigens, Surface↗
PubMed1986

Retention and subcellular distribution of 67Ga in normal organs.

Using normal rats, retention values and subcellular distribution of 67Ga in each organ were investigated. At 10 min after administration of 67Ga-citrate the retention value of 67Ga in blood was 6.77% dose/g, and this value decreased with time. The values for skeletal muscle, lung, pancreas, adrenal, heart muscle, brain, small intestine, large intestine and spinal cord were the highest at 10 min after administration, and they decreased with time. Conversely, this value in bone increased until 10 days after injection. But in the liver, kidney, and stomach, these values increased with time after administration and were highest 24 h or 48 h after injection. After that, they decreased with time. The value in spleen reached a plateau 48 h after administration, and hardly varied for 10 days. From the results of subcellular fractionation, it was deduced that lysosome plays quite an important role in the concentration of 67Ga in small intestine, stomach, lung, kidney and pancreas; a lesser role in its concentration in heart muscle, and hardly any role in the 67Ga accumulation in skeletal muscle. In spleen, the contents in nuclear, mitochondrial, microsomal, and supernatant fractions all contributed to the accumulation of 67Ga.

Animals↗
PubMed1985

A study on the amount of high-mobility-group chromatin proteins in T-cells at different stages of differentiation.

The amounts of high-mobility-group proteins (HMG) 1 and 2 in different mouse T-cell populations are studied. It is shown that the quantity of HMG 1 and 2 is different in functionally distinct T-cells. The level of these proteins in thymus cells is higher than in cortisone-resistant thymocytes and peripheral T-cells; it increases in the cytotoxic cells generated in mixed lymphocyte culture. The quantity of HMG is negligible in memory T-cells and increases when the latter cells are stimulated again. The differences found in the levels of HMG 1 and 2 could be related to the rate of cell proliferation and to the changes in chromatin structure at each functional stage of differentiating T-cells.

Animals↗